Dimethyl Carbonate

Dimethyl carbonate (DMC) is an organic compound that is colourless and flammable. It exhibits desirable properties such as good solvency, low toxicity and high reactivity with other chemicals. This compound has found use as a methylating agent and more recently as a solvent that is exempt from the restrictions placed on most volatile organic compounds (VOCs) in the US. DMC is also often considered to be a green reagent as it biodegrades readily in the atmosphere and is non-toxic. As such, it has found several applications in chemical synthesis, biocatalysis and batteries.

Manufacturing Process

World production in 1997 was estimated at 1000 barrels a day, and is limited to Asia, Middle East and Europe. Traditionally, it is prepared by the reaction of phosgene and methanol with methyl chloroformate forming as an intermediate.

COCl₂ + CH₃OH → CH₃OCOCl + HCl

CH₃OCOCl + CH₃OH → CH₃OCO₂CH₃ + HCl

However due to the high toxicity of phosgene, DMC is now manufactured through other methods such as the transesterification of ethylene carbonate or propylene carbonate with methanol to yield ethylene glycol or propylene glycol as the side product.

Coatings, Adhesives, Resins: Dimethyl carbonate has numerous applications in end-use industries. Due to its desirable chemical properties, it is vastly used as a solvent in making coatings, adhesives and cleaning agents. DMC is also used as an environmentally friendly solvent in cleaning agents.

Electronic Materials: Dimethyl carbonate is an indispensable part of the Li-ion batteries industry owing to its usage as an electrolyte. DMC is experiencing a rapid increase in demand for use in notebook PCs and cell phones. In addition, the demand is also expected to grow for use in hybrid electric vehicles (HEVs) and plug-in hybrid electric vehicles (PHEVs).

Pharmaceutical and Fine chemicals: DMC is also used as a raw material for organic synthesis, and in reactions that include methylation, carbonylation, and carbomethoxylation. A large captive use of dimethyl carbonate is for the production of diphenyl carbonate through transesterification with phenol. Diphenyl carbonate is a widely used raw material for the synthesis of bisphenol-A-polycarbonate in a melt polycondensation process